New & emerging live cell imaging techniques for quantitative measurements of molecular dynamics. (#88)
Techniques which couple quantitative measurements of molecular processes within live cells with simultaneous imaging of the cellular locations where they are occurring offer tremendous insights into a range of molecular processes. The rate of movement of individual molecules in live cells can be measured using fluorescently-labelled forms of the molecules of interest. However measuring molecular movement in live cells with high spatial and temporal resolution as well as high sensitivity and minimal perturbation of the cell poses significant challenges. A suite of techniques have now been developed which address different spatial resolutions and time domains for measuring molecular dynamics, such as rates and direction of movement and aggregation of molecules (monomers, dimers, etc). Some of these techniques can analyse relative movement / aggregation of one or two species of labelled molecules, with very high spatial and temporal resolution as well as single molecule sensitivity. Such techniques can provide accurate quantification of dynamic processes including diffusion, velocity, binding and rate constants from imaging molecular processes in live cells. The presentation will include confocal fluorescence correlation spectroscopy, raster image correlation spectroscopy, number and brightness analysis and optical pharmacokinetics drawing on examples from our own work with native neurons and by others studying virus-cell interactions.